112 BIKDS 



It is interesting to note that evidence of the survival 

 value of protective colouring is accumulating. The 

 Italian naturalist Cesnola, for instance, tethered green 

 mantises first among green vegetation and then among 

 brown. All the former survived after seventeen days, all 

 the latter were killed by birds and ants in eleven days. 

 This is very important, since it demonstrates that natural 

 selection sifts with a purpose, that it eliminates dis- 

 criminately and in virtue of the possession of certain 

 qualities. The theory that evolution has proceeded by 

 luck or accident is, as Samuel Butler truly held, " the 

 most absolute denial of God conceivable." 



In another sense, all animals are protectively coloured 

 as a kind of external symbol or manifestation of their 

 fitness to their environment. The visible harmony be- 

 tween animals and their homes illustrates the biological 

 inter-relationship between organism, function, and 

 environment. 



In a third sense, protective colouring is simply Nature's 

 good taste. An animal that sticks out of its environment 

 (as the imported pheasant does in all months except 

 October) or blends inharmoniously with it offends artistic 

 canons. 



In a fourth sense, protective colouring is a prudent check 

 upon the violent exuberance of life, and without it we 

 should be spectators of a mad riot of colour, a Futurist 

 exhibition. Humming birds and coral fishes, for instance, 

 which are so radiantly prismatic in colouring, have few 

 or no natural enemies. 



In a fifth sense, protective colouration is a fine example 

 of the interplay in nature between use and beauty, an 

 association which, when applied on a higher turn of the 

 spiral to human life, is the central doctrine of Morris and 

 Ruskin. Make things for use and not for profit, they 

 said, and you will find that the product itself is a thing 

 of beauty. Nature endorses and illustrates the teaching. 

 Mr. Barton's reference to the terns' white breasts is 



